Abstract:
We propose to study the orientation of galaxies in clusters that
show strong major axis alignments with their nearest cluster neighbors.
We want to test theories of structure formation in which clusters of
galaxies form in large scale filamentary superstructures by accretion of
galaxies along preferred directions. In such a scenario we expect to
see alignments of galaxies with their parent cluster position angle,
especially in dynamically young clusters where relaxation processes have
not yet erased such an alignment signature. We propose to conduct a
deep wide field multicolor imaging observations survey to detect cluster
galaxies out to the outskirts of their parent clusters, to measure the
ellipticity distribution for the different galaxy morphological types,
since the alignment signal could be galaxy-type dependent, and to reduce
projection effects. We will also study the dynamical effects by
quantifying the galaxy luminosity function and density profiles.